Depression container

ABSTRACT

In an aspect, a depression container includes a vessel, a cover, a pump, a pressure-activated switch and a power supply. The vessel includes an open end. The cover is used for sealing the open end of the vessel. The pump is used for drawing air out of the vessel. The pressure-activated switch is used for controlling ON and OFF of the pump. The pressure-activated switch detects the pressure in the vessel, and turns on the pump when the pressure is higher than a predetermined upper limit, and turns off the pump when the pressure is lower than a predetermined lower limit. The pressure-activated switch and the pump are powered by the power supply. In another aspect, a depression container includes a vessel, a cover, a pump, a pressure-activated switch and a power supply. The vessel includes an open end. The cover is used for sealing the open end of the vessel. The pump is used for drawing air out of the vessel. The pressure-activated switch and the pump are powered by the power supply. The pressure-activated switch is used for controlling ON and OFF of the pump. The pressure-activated switch detects a pressure difference resulting from closure of the open end of the vessel by the cover, and turns on the pump so as to draw air out of the vessel, and turns off the pump when the pressure in the vessel is lower than a predetermined lower limit.

CROSS REFERENCE

[0001] This is a continuation-in-part application of U.S. patentapplication Ser. No. 09/883,813 filed on Jun. 18, 2001.

BACKGROUND OF INVENTION

[0002] 1. Field of Invention

[0003] The present invention relates to a depression container equippedwith a pump that can be activated when the pressure in the depressioncontainer is above a value.

[0004] 2. Related Prior Art

[0005] A typical depression container includes a check valve. A userdraws air out of the depression container via the check valve with amanual pump including a piston and a cylinder, thus reducing thepressure in the depression container to a low valve. This reduces therisk of articles in the depression container getting wetted or rotten,thus lengthening the preservation period. It is, however, troublesomeand labor-intensive for the user to reciprocate the piston relative tothe cylinder. In addition, the user cannot know the pressure in thedepression container. Furthermore, the depression container cannotprovide an adequate sealing effect so that the pressure in thedepression container may rise after some time and adversely affect thepreservation of the articles therein.

SUMMARY OF INVENTION

[0006] It is an objective of the present invention to provide adepression container that can automatically draw air out of it after acover seals its open end. The pressure in the depression container isreduced to a predetermined value.

[0007] It is another objective of the present invention to provide adepression container that shows the value of the pressure. Moreover, thedepression container allows a user to set a value of the pressuredesired for preserving articles.

[0008] It is a further objective of the present invention to provide adepression container that can maintain the pressure therein under apredetermined valve for a long time.

[0009] In accordance with a first aspect of the invention, a depressioncontainer includes a vessel, a cover, a pump, a pressure-activatedswitch and a power supply. The vessel includes an open end. The cover isused for sealing the open end of the vessel. The pump is used fordrawing air out of the vessel. The pressure-activated switch is used forcontrolling ON and OFF of the pump. The pressure-activated switchdetects the pressure in the vessel, and turns on the pump when thepressure is higher than a predetermined upper limit, and turns off thepump when the pressure is lower than a predetermined lower limit. Thepressure-activated switch and the pump are powered by the power supply.

[0010] In accordance with a second aspect of the invention, a depressioncontainer includes a vessel, a cover, a pump, a pressure-activatedswitch and a power supply. The vessel includes an open end. The cover isused for sealing the open end of the vessel. The pump is used fordrawing air out of the vessel. The pressure-activated switch and thepump are powered by the power supply. The pressure-activated switch isused for controlling ON and OFF of the pump. The pressure-activatedswitch detects a pressure difference resulting from closure of the openend of the vessel by the cover, and turns on the pump so as to draw airout of the vessel, and turns off the pump when the pressure in thevessel is lower than a predetermined lower limit.

[0011] In the second aspect of the present invention, when the pressurerises and exceeds an upper limit, the pressure-activated switch turns onthe pump again until the pressure is reduced to the lower limit. Thus,the articles in the vessel can be preserved for a long time by means ofmaintaining the pressure in the vessel under a predetermined lowpressure suitable for preservation of articles.

[0012] Other objects, novel features and advantages of the inventionwill become more apparent from the following detailed description whentaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0013]FIG. 1 is a perspective view of a depression container inaccordance with the present invention.

[0014]FIG. 2 is an exploded perspective view of the depression containerin accordance with the present invention.

[0015]FIG. 3 is a sectional view of an upper portion of the depressioncontainer in accordance with the present invention.

[0016]FIG. 4 is a sectional view similar to FIG. 3, illustratingoperation of the depression container upon closing of a cover.

[0017]FIG. 5 is a sectional view similar to FIG. 4, wherein the cover ismoved to its completely closed position.

[0018]FIG. 6 is a perspective view illustrating a modified embodiment ofthe depression pump in accordance with the present invention.

[0019]FIG. 7 is an exploded perspective view illustrating a furthermodified embodiment of the depression pump in accordance with thepresent invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0020] Referring to FIGS. 1 through 3, in accordance with a firstembodiment of the present invention, a depression container includes avessel 2, a cover 4, a pump 6 and a pressure-activated switch 8.

[0021] The vessel 2 defines a compartment 10 for receiving articles tobe preserved. The vessel 2 includes a closed lower end and an open upperend.

[0022] The cover 4 can be mounted on the open upper end of the vessel 2so as to close the compartment 10. An annular seal 12 can be mounted onthe open upper end of the vessel 2 before the cover 4 in order to sealthe compartment 10.

[0023] A box 14 is formed on the vessel 2. The box 14 defines a space 16in order to receive the pump 6 and the pressure-activated switch 8. Afirst orifice 18 and a second orifice 20 are defined in the vessel 2.The compartment 10 is communicated with the space 16 through the firstorifice 18 and the second orifice 20. Two parallel first walls 22 andtwo parallel second walls 24 are formed on the vessel 2, located in thebox 14, best shown in FIG. 2. Each of the first walls 22 includes twoslots 26, for example. Each of the second walls 24 includes two slots28.

[0024] The pump 6 includes a casing 30 and a duct 32 extending from thecasing 30. The casing 30 includes two parallel sides on each of whichtwo engaging members 34 are formed. The engaging members 34 are engagedwith the slots 26 so as to securely mount the pump 6 on the vessel 2, inthe box 14. Further referring to FIG. 4, an airtight sleeve 36 ismounted on the duct 32. The sleeve 36 is inserted through the firstorifice 18 in order to prevent leakage of air through the first orifice18.

[0025] The pressure-activated switch 8 includes a casing 38 and a duct40 extending from the casing 38. The casing 38 includes two parallelsides on each of which an engaging member 42 is formed. The engagingmembers 42 are engaged with the slots 28 so as to securely mount thepressure-activated switch 8 on the vessel 2, in the box 14. Furtherreferring to FIG. 5, an airtight sleeve 44 is mounted on the duct 40.The sleeve 44 is inserted through the second orifice 20 in order toprevent leakage of air through the second orifice 20.

[0026] The pressure-activated switch 8 includes a differential typepressure transducer 46 that includes a sensor 48. The differential typepressure transducer 46 is received in the casing 38 so that the sensor48 is received in the duct 40. The pressure-activated switch 8 includesa control chip 50 received in the casing 38. The differential typepressure transducer 46 is electrically connected with the sensor 48 andthe control chip 50. The control chip 50 is electrically connected withthe pump 6 through female and male connectors 52 and 54.

[0027] A wire 56 includes an end electrically connected with the controlchip 50 and an opposite end electrically connected with an adaptor 58.The control chip 50 can be electrically connected with an external ACpower supply (not shown) via the wire 56 in order to power the pump 6and the pressure-activated switch 8.

[0028] The pressure transducer 46 outputs a voltage in response to adifference between a reference pressure (the pressure in the atmospherefor example) and a detected pressure in the compartment 10 of the vessel2. Namely, the output voltage of the pressure transducer 46 is inproportion to the pressure difference. In an embodiment, the outputvoltage is 3.3V if the detected pressure is equal to or above a firstthreshold (1.15 atm for example). The output voltage is 1.2 V if thedetected pressure is equal to or below a second threshold (0.1 atm forexample). The output voltage is 1.5V if the detected pressure is equalto or above a third threshold (0.25 atm for example).

[0029] A set of controlling programs is recorded in the control chip 50.The control chip 50 can be switched between two logic control modes M1and M2 via operation of a switch 60 electrically connected with thecontrol chip 50. The switch 60 is mounted on a panel 62 that can beattached to the box 14 in order to close the space 16. In the controlmode M1, the pump 6 is activated when the output voltage of the pressuretransducer 46 is higher than or equal to 3.3 V. The pump 6 is turned offwhen the output voltage of the pressure transducer 46 is lower than orequal to 1.2 V. In the control mode M2, the pump 6 is activated when theoutput voltage of the pressure transducer 46 is higher than or equal to1.5 V. The pump 6 is turned off when the output voltage of the pressuretransducer 46 is lower than or equal to 1.2 V.

[0030] In use, referring to FIG. 6, the switch 60 is firstly switched tothe control mode M1, and the cover 4 is mounted on and thus encloses thevessel 20. During closing of the cover 4, i.e., the cover 4 is moveddownward relative to the vessel 20, the air inside compartment 10 of thevessel 2 is compressed and thus generates a temporary pressure greaterthan 1.15 atm. The pressure transducer 46 of the pressure-activatedswitch 8 detects such a temporary pressure and outputs a voltage higherthan 3.3 V. The pump 6 is thus activated under the control of thecontrol chip 50, thus drawing air out of the vessel 2. The pressure inthe vessel 2 is accordingly reduced. When the pressure in the vessel 2is equal to or below 0.1 atm, the output voltage of the pressuretransducer 46 is lower than 1.2 V. The pump 6 is thus turned off.

[0031] Referring to FIGS. 4 and 5, the switch 60 is switched to thecontrol mode M2 after depression. If the pressure in the vessel 2 risesas a result of entrance of ambient air into the vessel 2, the sensor 44detects the pressure and the pump 6 is turned on when the pressure inthe vessel 2 is equal to or above 0.25 atm upon outputting an outputvoltage higher than 1.5 V. When the pressure inside the vessel 2 isequal to or lower than 0.1 atm, the pressure transducer 46 outputs avoltage lower than 1.2 V to turn off the pump 6. Thus, the pressure inthe vessel 2 is kept at about 0.1 atm.

[0032] The switch 60 and the control modes M1 and M2 can be simplified.For example, the control mode M1 is OFF and the control mode M2 is ON.More specifically, the pressure transducer 46 is turned on when in thecontrol mode M2 and is turned off when in the control mode M1. Thus,when in use, the user may attach the cover 4 to the vessel 2 and switchto the control mode M2 after the cover 4 is in position. The pump 6 isturned on when the pressure in the vessel 2 is equal to or above 0.25atm and the pump 6 is turned off when the pressure in the vessel 2 isequal to or lower than 0.1 atm.

[0033]FIG. 7 shows a depression container according to a secondembodiment of the present invention. The second embodiment is differentfrom the first embodiment in that the first plates 22 are replaced witha collar 64 including a thread 66 formed on an internal face, that thecasing 30 is replaced with a cylindrical casing 68 including a thread 70formed thereon, that the second plates 24 are replaced with a collar 72including a thread 74 formed on an internal face and that the casing 38is replaced with a cylindrical casing 76 including a thread 78 formedthereon. The thread 70 can be engaged with the thread 66, thus mountingthe casing 68 on the collar 64. The thread 78 can be engaged with thethread 74, thus mounting the casing 68 on the collar 64. The secondembodiment is otherwise identical to the first embodiment.

[0034] Although the invention has been explained in relation to itspreferred embodiment, it is to be understood that many other possiblemodifications and variations can be made without departing from thescope of the invention as hereinafter claimed.

What is claimed is:
 1. A depression container including: a vesselincluding a compartment with an open end; a cover for enclosing the openend of the vessel, thus sealing the compartment; a pump mounted on andcommunicated with the vessel for drawing air from the compartment; and apressure-activated switch mounted on and communicated with the vesselfor detecting a pressure in the compartment, turning on the pump whenthe pressure is higher than an upper limit, and turning off the pumpwhen the pressure is lower than a lower limit.
 2. The depressioncontainer according to claim 1 wherein the vessel defines an orificecommunicated with the compartment, and the pump includes a duct insertedthrough the orifice.
 3. The depression container according to claim 2including an airtight sleeve mounted on the duct and inserted throughthe orifice.
 4. The depression container according to claim 1 whereinthe vessel defines an orifice communicated with the compartment, and thepressure-activated switch includes a duct inserted through the orifice.5. The depression container according to claim 4 including an airtightsleeve mounted on the duct and inserted through the orifice.
 6. Thedepression container according to claim 1 wherein the vessel includes acollar with a thread formed on an internal face, and the pump includes acylindrical casing formed with a thread for engagement with the threadof the collar.
 7. The depression container according to claim 1 whereinthe vessel includes a collar with a thread formed on an internal face,and the pressure-activated switch includes a cylindrical casing formedwith a thread for engagement with the thread of the collar.
 8. Thedepression container according to claim 1 including a box formed on thevessel for receiving the pump.
 9. The depression container according toclaim 1 including a box formed on the vessel for receiving thepressure-activated switch.
 10. A depression container including: avessel including a compartment with an open end; a cover for enclosingthe open end of the vessel, thus sealing the compartment; a pump mountedon and communicated with the vessel for drawing air from thecompartment; and a pressure-activated switch mounted on and communicatedwith the vessel for detecting a pressure difference resulting from amotion of closing the vessel via the cover, turning on the pump so as todraw air out of the compartment, and turning off the pump when anpressure in the compartment detected by the pressure-activated switch islower than a lower limit.
 11. The depression container according toclaim 10 wherein the pressure-activated switch includes a differentialtype pressure transducer and a control chip electrically connected withthe pump, and the pressure transducer includes a sensor inserted intothe compartment for detecting the pressure in the compartment andsending a voltage to the control chip in response to a differencebetween a reference pressure and the pressure detected by the sensor.12. The depression container according to claim 11 wherein the referencepressure is the atmosphere pressure.
 13. The depression containeraccording to claim 10 wherein the vessel defines an orifice communicatedwith the compartment, and the pump includes a duct inserted through theorifice.
 14. The depression container according to claim 13 including anairtight sleeve mounted on the duct and inserted through the orifice.15. The depression container according to claim 10 wherein the vesseldefines an orifice communicated with the compartment, and thepressure-activated switch includes a duct inserted through the orifice.16. The depression container according to claim 15 including an airtightsleeve mounted on the duct and inserted through the orifice.
 17. Thedepression container according to claim 10 wherein the vessel includes acollar with a thread formed on an internal face, and the pump includes acylindrical casing formed with a thread for engagement with the threadof the collar.
 18. The depression container according to claim 10wherein the vessel includes a collar with a thread formed on an internalface, and the pressure-activated switch includes a cylindrical casingformed with a thread for engagement with the thread of the collar. 19.The depression container according to claim 7 including a box formed onthe vessel for receiving the pump.
 20. The depression containeraccording to claim 7 including a box formed on the vessel for receivingthe pressure-activated switch.